bronch                 package:MCPAN                 R Documentation

_R_o_d_e_n_t _b_r_o_n_c_h_i_a_l _c_a_r_c_i_n_o_m_a _d_a_t_a

_D_e_s_c_r_i_p_t_i_o_n:

     In a long term rodent carcinogenicity study on female B6C3F1 mice,
      the effect of vinylcyclohexene diepoxide on the incidence of
     murine alveolar/bronchiolar tumors was assessed. The mice were
     exposed to 0 mg/ml, (group 0), 25 mg/ml (group 1), 50 mg/ml (group
     2), and 100 (group 3) mg/ml, with 50 animals per group.

_U_s_a_g_e:

     data(bronch)

_F_o_r_m_a_t:

     A data frame with 200 observations on the following 3 variables.

     _g_r_o_u_p a factor with levels 0, 1, 2, 3, labelling the control and
          the three dose groups

     _Y a logical vector, indicating whether a tumour was present at
          time of death (if TRUE), or not (if FALSE) 

     _t_i_m_e a numeric vector, the time of death, counted in days? from
          begin of the study

_D_e_t_a_i_l_s:

     Not yet checked for consistency with the source!

_S_o_u_r_c_e:

     Piegorsch WW and Bailer AJ (1997): Statistics for environmental
     biology and toxicology. Chapman and Hall, London. Table 6.5, page
     238.

_R_e_f_e_r_e_n_c_e_s:

     Portier cJ and Bailer AJ (1989): Testing for increased
     carcinogenicity using survival-adjusted quantal response tests.
     Fundamental and Applied Toxicology 12, 731.

_E_x_a_m_p_l_e_s:

     data(bronch)
     # raw tumour counts:

     table(bronch[c("group","Y")])

     # groupwise times of death:

     boxplot(time ~ group, data=bronch, horizontal=TRUE)

     # Using poly3estf, we can produce the
     # summary statistics as presented in 
     # Table 6.6, page 239, of Piegorsch and Bailer (1997):

     poly3estf(status=bronch$Y, time=bronch$time, f=bronch$group)

